1. Technical Field
This invention relates to a flexible energy absorbing material, preferably in sheet form, and to methods of manufacture thereof.
2. Background of Related Art
Known impact protection solutions currently available tend to fall into two types, namely a rigid exterior shell which can be uncomfortable to wear (e.g. roller blade or skateboard knee or elbow pads) or foam or foam laminate pads (e.g. inserts for ski clothing) which provide poor levels of protection.
There is therefore a need to provide an energy absorbing material which is both light and flexible and therefore comfortable to wear while still being able to dissipate and absorb shock impacts applied to it thereby providing effective protection for the wearer.
In my earlier published UK patent application No. 2349798, I describe and claim a protective member which uses an energy absorbing material which remains soft and flexible until it is subjected to an impact when it becomes rigid, said material being encapsulated in a flexible sealed envelope formed with one or more convolutions thereon each having an apex directed towards the direction of impact whereby an impact force applied to the or each apex is absorbed as the material becomes rigid.
The preferred energy absorbing material is a dilatant material which acts very much like a fluid when soft. It therefore needs to be contained within a sealed flexible envelope to enable it to be used as a protective member. If, for instance, the envelope is ruptured accidentally, the dilatant material would escape through the punctured hole in the envelope. Because of the need for the sealed envelope, the protective members can be expensive to manufacture and they have to be user specific so a dedicated moulding process is needed to manufacture them.